Chairman of the Indian Space Research Organisation Dr G Madhavan Nair speaks to NDTV  about Chandrayaan Mission.

Pallava Bagla: What has been the performance of Chandrayaan mission till now?

G Madhavan Nair: We are extremely happy with the Chandrayaan mission. As you know in November last year we took to the moon and since then we have been operating systematically.

Pallava Bagla: So would be it ok to say that you have had a dream run till now?

G Madhavan Nair: Yes, I will say as far as the mission objectives are concerned, it has been a 100 per cent success. We have achieved whatever we set to achieve through this and so far the performance I think has been to the full satisfaction of our scientific community.

Pallava Bagla: I believe something has malfunctioned, some critical malfunction has happened on the Chandrayaan-1; what has really happened?

G Madhavan Nair: You know the space missions - they are very complex. There are instances of problems on board and we are also not spared from this. But as you know that normally we provide for redundancies on board and that is supposed to take care of, in case of a problem. The first thing what we had encountered was when it was put in the 100 kilometre orbit. It simply reached the stage of thermal runaway. The entire spacecraft would have been baked and would have been simply lost.

Pallava Bagla: Baked and lost!

G Madhavan Nair: That was the scenario one month after the launch. But fortunately our mission team - they worked out a strategy by which it was oriented in the right direction and also the thermal management by putting off some of the instruments which are not vital and then looking away into the deep space - with that we have managed and since then we have really run the instruments according to what we wanted.

Pallava Bagla: So, for a layman would it be ok to say that the spacecraft was overheating?

G Madhavan Nair: Yes, it had reached a stage where many of the electronics would have failed. Yes indeed some of the power supply related instruments failed but fortunately we were able to energise the redundant units and keep it alive all this time. And of course this has been going on for quite sometime but unfortunately during the last month we have lost one vital sensor - the star sensor. Like in old days you looked at stars to fix the direction. So we have an onboard electronic instrument which is doing this and this was required for precise pointing. With the loss of that we were really worried and normally the mission could be lost but to the credit of the ISRO scientific team, they have worked out a very innovative way of overcoming this. In fact you know there are cameras on board on Chandrayaan that are looking at the moon and there are known spots on the moon which are well defined. Similarly the Chandrayaan is looking at a ground station at Bylalu. So that's also a fixed location. Using this vector they have evolved a mathematical formulation by which we were able to recapture the orientation and using the onboard gyros which are supposed to be, you know, the redundant pieces, we were able to run the mission as satisfactorily as earlier. So I can say that these two events which would simply have led to a mission catastrophe were managed by ISRO's team very efficiently.

Pallava Bagla: So in a layman's term, would it be ok to say that the satellite is orbiting the moon but you were not able to locate specific things on the moon, through the loss of the star sensor?

G Madhavan Nair: If we did not have a redundant system we would have lost. Even the gyroscope which is there, it has limitation. You know what happens is it has got a drift with time. So there, the innovation of our scientists came in and within a very short span of time they have formulated, validated the software and conducted sufficient experiment. Today it is able to precisely point to the lunar location as with the star sensor, so we are not compromising anything on board the spacecraft now.

Pallava Bagla: So you had a failure but you have been able to recover from that?

G Madhavan Nair: Absolutely. This actually as I mentioned earlier, the space missions, we have to be anticipating some sort of a problem or another and normally we provide a certain amount of redundancies. When it goes beyond that, then the mission will get lost. There are instances in which many missions were lost in their early phases but I will say that we were lucky that we have completed almost all the mission objectives.

Pallava Bagla: So would this be called jugaad technology? Something failed and because you have learnt the art of maintaining these things you are able to put some innovative things together - would it be jugaad, would one say?

G Madhavan Nair: I would say that it is the imagination, the promptness of action and also the type of the solutions which we find - they are very unique. You know, we do not have to go through a situation where if something fails then we can go with another mission immediately; so we try to see that these missions are very carefully attended to and we do not leave anything to chance. Every spacecraft which is there, it is being monitored through our telemetry and tele-command system by a human process. Every spacecraft has a 24-hour watch kept by our people. And that also our senior people intervene at the right time, so they will find a right solution and the whole thing is managed by them.

Pallava Bagla: So right now, is the spacecraft working normally?

G Madhavan Nair: Well I can only quote a scientist. They have given 'n' number of action items or more to image or to collect the data etc. During this season, every request from the scientists has been serviced.

Pallava Bagla: So have there been any key findings from the machine till now?

G Madhavan Nair: Well one thing I can say - the features which are revealed by the terrain mapping camera is very unique and to this resolution of 10 metres is the first of its kind. Of course it has to be further analysed and codified and catalogued and all those exercises are going on. The terrain mapping which is done by the laser instrument is also very interesting data. One can really dig into the origins of the craters and so on. The mineral mapper - it has more or less looked at the entire surface of the moon and they were able to identify the locations where it is rich in iron-ore, where there are calcium deposits, magnesium deposits and even titanium, which is supposed to absorb the helium 3 - such locations have been seen. But again we have to really systematically code it - that exercise is going on.

Pallava Bagla: Are there any Indian instruments which will suffer completely because of this failure because I believe you have had to raise the orbit from 100 to 200 kms?

G Madhavan Nair: But that was done for an entirely different purpose. You know the primary objectives have been met at a 100 km orbit. Then you know every month we have to do a nudging operation to keep that orbit live. By any chance if any problem comes in that operation we may crash land on the moon. Since the primary objectives were completed we raised the orbit to nearly 200 kms - that is a stable orbit. Even if you do not apply correction it may vary about 20-30 kms but that is stable. Also there is another objective. We can try to analyse the perturbations of the gravitational field at this height. So that is another reason. But at the same time some of the instruments which we are having has a resolution of, let us say, 10 metres that will go to 20 metres but advantage is we will cover a large